Trouble in omnibusF4 pro_OSD/unable ALThold

I had some trouble while I use this controller.onmibus f4 pro v2,AP3.9.4
1.In Cruise mode,the aultitude slowly rising,approximate it’s climb 100 meters per 2 kilomerters far.and I wander to kown why?A black sponge had been covered on the controller.
2.I’d like to flight in auto mission without RC in(transmitter),write flight plan in f4 by bluetooth.then I need to observed some Important parameters such as BAT/current/waypoint/ distance so on, then I add a vedio TX but I don’t want to adding a camera on my plane.just OSD is ok…funning is osd BAT_Y I set to 14,I can’t see it when I power on F4 ,seems it is hided in the bottom,when I add a camera,it’s showing I set osd BAT_Y to 12,it’s work’‘ok’'but not write in eeprom?F4 powered again,it’s hided again…

any reply would be appreciated.